IT SEEMS UNLIKELY that Princess Haifa al-Faisal, the wife of Saudi Arabia's veteran ambassador to Washington, knowingly provided funds to some of the Saudi militants who participated in the 9/11 conspiracy. The financial connection itself is tenuous: According to the news reports that appeared over the weekend, the princess authorized checks to a Saudi woman reportedly suffering from medical problems, and some of that money may have been passed to another Saudi man, who, in turn, helped two of the hijackers rent an apartment in San Diego. There appears to be no evidence so far that any of the money donated by the princess ended up in the hijackers' hands, or even that the Saudi intermediaries knew they were assisting terrorists. Still, it is unsettling to think how few degrees of separation apparently existed between such a senior Saudi figure -- and one so close to the U.S. Saudi relationship -- and the men who later flew a hijacked airliner into the Pentagon.

The uproar over the matter also underlines a larger truth: that 14 months after 9/11, the connections between Saudi Arabia and militant Islam, and the kingdom's willingness to cooperate in the war on terrorism, remain disturbingly unclear. Saudi authorities have never given U.S. investigators full access to information about the 15 hijackers who were Saudi nationals. Washington's attempts to freeze the bank accounts and assets of Saudi nationals suspected of providing funding to al Qaeda have frequently been resisted by Riyadh. Whether or not the ambassador's wife is involved, there are strong indications that Saudi wealth continues to flow to extremist Islamic movements and institutions that foment the ideology of terrorism, and perhaps the terrorist networks themselves. Many senior Saudi officials appear eager to preserve the long-standing alliance between the royal family and the United States, and high-level goodwill delegations have been flocking to Washington. Yet those pro-Western Saudis appear unable, or unwilling, to undertake the difficult domestic battles that full cooperation in the war on terrorism would require -- such as reining in powerful clergy and religious foundations.

Hampered by internal debate, the Bush administration has been uncertain and inconsistent in handling this difficult problem. The White House reportedly is considering some tougher tactics, such as giving the Saudi government a deadline for cracking down on suspected terrorist financiers identified by Washington. But the United States still badly needs Saudi Arabia's reliable oil supplies and would like to use its military bases in the event of a war on Iraq. Stronger pressure on the Saudi rulers could endanger these interests, or prompt the collapse of the royal family and the rise of a regime that was explicitly anti-American.

Like the Pakistani regime of Pervez Musharraf, the Saudi government increasingly looks like a U.S. ally only in comparison with some of the frightening alternatives. Even with stronger pressure, its ability, or even willingness, to assist in a war against Islamic extremism will be strictly circumscribed. Episodes such as the controversy over Princess Haifa ought to reinforce the point that the prevailing political order in the Middle East is incompatible with America's interests. Changing it, whether by means of gradual political and economic liberalization, or through the removal of aggressive dictators such as Saddam Hussein, is a challenge that the United States must take up.